Det Insp Waddell says police have serious concerns for Ms Smith's welfare and are treating her disappearance as suspicious.

"Our inquiries have revealed that Leisl's mobile phone was used in the days immediately after she was reported missing, however, she has not accessed her bank accounts or sought any assistance since that time," he said.

Investigations are continuing and police are appealing for anyone with information to contact Crime Stoppers on 1800 333 000.